Digital cameras include a two-dimensional pixel array. Each pixel includes a light sensitive element that converts photons to an analog signal. The light sensitive elements can include photodiodes, phototransistors, photo-gates, hole accumulation diodes, pinned diodes, avalanche diodes, buried accumulation and transfer layer devices.
Various prior art pixels are known. The most commonly used pixels are either CCD pixels or CMOS pixels.
Each pixel provides an analog signal in response to light that interacts with the light sensitive element.
A pixel has a dynamic range. The dynamic range is defined by a maximal detection signal and a minimal detection signal. In various applications there is a need to expand the dynamic range of the pixels.
There is a need to provide efficient methods and devices for reading a pixel and thereby expanding the dynamic range of the pixel.